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00022 #include "libavutil/intreadwrite.h"
00023 #include "avformat.h"
00024 #include "riff.h"
00025
00026 #define DXA_EXTRA_SIZE 9
00027
00028 typedef struct{
00029 int frames;
00030 int has_sound;
00031 int bpc;
00032 uint32_t bytes_left;
00033 int64_t wavpos, vidpos;
00034 int readvid;
00035 }DXAContext;
00036
00037 static int dxa_probe(AVProbeData *p)
00038 {
00039 int w, h;
00040 if (p->buf_size < 15)
00041 return 0;
00042 w = AV_RB16(p->buf + 11);
00043 h = AV_RB16(p->buf + 13);
00044
00045 if (p->buf[0] == 'D' && p->buf[1] == 'E' &&
00046 p->buf[2] == 'X' && p->buf[3] == 'A' &&
00047 w && w <= 2048 && h && h <= 2048)
00048 return AVPROBE_SCORE_MAX;
00049 else
00050 return 0;
00051 }
00052
00053 static int dxa_read_header(AVFormatContext *s, AVFormatParameters *ap)
00054 {
00055 ByteIOContext *pb = s->pb;
00056 DXAContext *c = s->priv_data;
00057 AVStream *st, *ast;
00058 uint32_t tag;
00059 int32_t fps;
00060 int w, h;
00061 int num, den;
00062 int flags;
00063
00064 tag = get_le32(pb);
00065 if (tag != MKTAG('D', 'E', 'X', 'A'))
00066 return -1;
00067 flags = get_byte(pb);
00068 c->frames = get_be16(pb);
00069 if(!c->frames){
00070 av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");
00071 return -1;
00072 }
00073
00074 fps = get_be32(pb);
00075 if(fps > 0){
00076 den = 1000;
00077 num = fps;
00078 }else if (fps < 0){
00079 den = 100000;
00080 num = -fps;
00081 }else{
00082 den = 10;
00083 num = 1;
00084 }
00085 w = get_be16(pb);
00086 h = get_be16(pb);
00087 c->has_sound = 0;
00088
00089 st = av_new_stream(s, 0);
00090 if (!st)
00091 return -1;
00092
00093
00094 if(get_le32(pb) == MKTAG('W', 'A', 'V', 'E')){
00095 uint32_t size, fsize;
00096 c->has_sound = 1;
00097 size = get_be32(pb);
00098 c->vidpos = url_ftell(pb) + size;
00099 url_fskip(pb, 16);
00100 fsize = get_le32(pb);
00101
00102 ast = av_new_stream(s, 0);
00103 if (!ast)
00104 return -1;
00105 ff_get_wav_header(pb, ast->codec, fsize);
00106
00107 while(url_ftell(pb) < c->vidpos && !url_feof(pb)){
00108 tag = get_le32(pb);
00109 fsize = get_le32(pb);
00110 if(tag == MKTAG('d', 'a', 't', 'a')) break;
00111 url_fskip(pb, fsize);
00112 }
00113 c->bpc = (fsize + c->frames - 1) / c->frames;
00114 if(ast->codec->block_align)
00115 c->bpc = ((c->bpc + ast->codec->block_align - 1) / ast->codec->block_align) * ast->codec->block_align;
00116 c->bytes_left = fsize;
00117 c->wavpos = url_ftell(pb);
00118 url_fseek(pb, c->vidpos, SEEK_SET);
00119 }
00120
00121
00122 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00123 st->codec->codec_id = CODEC_ID_DXA;
00124 st->codec->width = w;
00125 st->codec->height = h;
00126 av_reduce(&den, &num, den, num, (1UL<<31)-1);
00127 av_set_pts_info(st, 33, num, den);
00128
00129
00130
00131
00132 if(flags & 0xC0){
00133 st->codec->height >>= 1;
00134 }
00135 c->readvid = !c->has_sound;
00136 c->vidpos = url_ftell(pb);
00137 s->start_time = 0;
00138 s->duration = (int64_t)c->frames * AV_TIME_BASE * num / den;
00139 av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);
00140
00141 return 0;
00142 }
00143
00144 static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
00145 {
00146 DXAContext *c = s->priv_data;
00147 int ret;
00148 uint32_t size;
00149 uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];
00150 int pal_size = 0;
00151
00152 if(!c->readvid && c->has_sound && c->bytes_left){
00153 c->readvid = 1;
00154 url_fseek(s->pb, c->wavpos, SEEK_SET);
00155 size = FFMIN(c->bytes_left, c->bpc);
00156 ret = av_get_packet(s->pb, pkt, size);
00157 pkt->stream_index = 1;
00158 if(ret != size)
00159 return AVERROR(EIO);
00160 c->bytes_left -= size;
00161 c->wavpos = url_ftell(s->pb);
00162 return 0;
00163 }
00164 url_fseek(s->pb, c->vidpos, SEEK_SET);
00165 while(!url_feof(s->pb) && c->frames){
00166 get_buffer(s->pb, buf, 4);
00167 switch(AV_RL32(buf)){
00168 case MKTAG('N', 'U', 'L', 'L'):
00169 if(av_new_packet(pkt, 4 + pal_size) < 0)
00170 return AVERROR(ENOMEM);
00171 pkt->stream_index = 0;
00172 if(pal_size) memcpy(pkt->data, pal, pal_size);
00173 memcpy(pkt->data + pal_size, buf, 4);
00174 c->frames--;
00175 c->vidpos = url_ftell(s->pb);
00176 c->readvid = 0;
00177 return 0;
00178 case MKTAG('C', 'M', 'A', 'P'):
00179 pal_size = 768+4;
00180 memcpy(pal, buf, 4);
00181 get_buffer(s->pb, pal + 4, 768);
00182 break;
00183 case MKTAG('F', 'R', 'A', 'M'):
00184 get_buffer(s->pb, buf + 4, DXA_EXTRA_SIZE - 4);
00185 size = AV_RB32(buf + 5);
00186 if(size > 0xFFFFFF){
00187 av_log(s, AV_LOG_ERROR, "Frame size is too big: %d\n", size);
00188 return -1;
00189 }
00190 if(av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size) < 0)
00191 return AVERROR(ENOMEM);
00192 memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);
00193 ret = get_buffer(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);
00194 if(ret != size){
00195 av_free_packet(pkt);
00196 return AVERROR(EIO);
00197 }
00198 if(pal_size) memcpy(pkt->data, pal, pal_size);
00199 pkt->stream_index = 0;
00200 c->frames--;
00201 c->vidpos = url_ftell(s->pb);
00202 c->readvid = 0;
00203 return 0;
00204 default:
00205 av_log(s, AV_LOG_ERROR, "Unknown tag %c%c%c%c\n", buf[0], buf[1], buf[2], buf[3]);
00206 return -1;
00207 }
00208 }
00209 return AVERROR(EIO);
00210 }
00211
00212 AVInputFormat dxa_demuxer = {
00213 "dxa",
00214 NULL_IF_CONFIG_SMALL("DXA"),
00215 sizeof(DXAContext),
00216 dxa_probe,
00217 dxa_read_header,
00218 dxa_read_packet,
00219 };